[Technical Field]
[0001] Various embodiments of the disclosure relate to a biometric liveness authentication
method and an electronic device.
[Background Art]
[0002] In line with development of digital technologies, there has been widespread use of
various types of electronic devices such as a mobile communication terminal, a personal
digital assistant (PDA), an electronic wallet, a smartphone, a tablet personal computer
(PC), and a wearable device. in order to support and enhance functions of such electronic
devices, the hardware part and/or software part of the electronic devices have been
continuously improved.
[0003] Meanwhile, in connection with biometric authentication technologies, a liveness detection
technology may refer to a technology for recognizing whether an image acquired from
a camera has been acquired by capturing an image of an actual person or by capturing
an image of a counterfeit (for example, paper on which a face is printed, 3D mask).
An electronic device may acquire a face image (or face data) from a camera disposed
on the front surface of the electronic device, may analyze the acquired face image,
and may determine whether the same corresponds to the actual user's face (for example,
live) or a fake through liveness authentication.
[Disclosure of Invention]
[Technical Problem]
[0004] Various embodiments may provide a method and a device for authenticating biometric
liveness by disposing a camera (for example, under display camera (UDC)) below a display
included in an electronic device, disposing at least one light source at a designated
distance from the camera, and randomly driving the light source.
[Solution to Problem]
[0005] An electronic device according to various embodiments of the disclosure may include
a display, a camera module disposed under the display, at least one light source disposed
to correspond to the camera module, a memory, and a processor operatively connected
to at least one among the display, the camera module, the light source, or the memory,
wherein the processor is configured to drive the camera module and the at least one
light source in response to a request for biometric authentication, acquire a face
image from the camera module, analyze the face image, based on the driven at least
one light source, and perform biometric authentication based on the analysis result.
[0006] A method for operating an electronic device according to various embodiments of the
disclosure may include driving a camera module, disposed under a display of the electronic
device, and at least one light source, disposed to correspond to the camera module,
in response to a request for biometric authentication, acquiring a face image from
the camera module, analyzing the face image, based on the driven at least one light
source, and performing biometric authentication based on the analysis result.
[Advantageous Effects of Invention]
[0007] According to various embodiments, one or more light sources among multiple light
sources may be randomly driven, and based on whether reflected light corresponding
to the number of driven light sources is detected from a face image acquired from
a camera, biometric liveness may be determined.
[0008] According to various embodiments, a camera and one or more light sources may be disposed
below a display without making a hole in the display, and different light sources
may be made to emit light randomly to diversify light-emitting patterns, thereby enhancing
security.
[0009] According to various embodiments, an infrared ray (IR) LED invisible to a user's
eyes may be used as a light source such that security can be enhanced, because a user
who has requested biometric authentication cannot be aware of the driven light source.
[0010] According to various embodiments, an IR filter may be utilized to selectively sense
only information in a designated wavelength so as to reduce the influence of whether
a display operates on images acquired by a camera, thereby enabling biometric liveness
detection even when the display is used.
[0011] According to various embodiments, biometric liveness detection is possible regardless
of peripheral light (low illumination or outdoor environment), and the intensity of
a light source may be adjusted such that biometric liveness detection is possible
regardless of the display transmittance.
[Brief Description of Drawings]
[0012]
FIG. 1 is a block diagram of an electronic device in a network environment according
to various embodiments.
FIGS. 2A and 2B are perspective views of an electronic device according to various
embodiments.
FIG. 3 is a partial cross-sectional view of an electronic device according to various
embodiments.
FIG. 4 is an enlarged cross-sectional view of an area including a camera module of
an electronic device according to various embodiments.
FIG. 5 illustrates an example in which a camera and at least one light source are
disposed in an electronic device according to various embodiments.
FIG. 6 is a flowchart illustrating a method for operating an electronic device according
to various embodiments.
FIG. 7 illustrates an example in which a reflected ray is detected from a user's eye
by a light source according to various embodiments.
FIGS. 8A and 8B illustrate an example of authenticating biometric liveness by randomly
driving a light source in an electronic device according to various embodiments.
FIGS. 9A and 9B illustrate another example of authenticating biometric liveness by
randomly driving a light source in an electronic device according to various embodiments.
FIG. 10 is a flowchart illustrating a biometric liveness authentication method of
an electronic device according to various embodiments.
FIG. 11 is a flowchart illustrating a biometric liveness authentication method of
an electronic device according to various embodiments.
FIG. 12 is a flowchart of a biometric-authentication and liveness-authentication method
of an electronic device according to various embodiments.
[Mode for the Invention]
[0013] Fig. 1 is a block diagram illustrating an electronic device 101 in a network environment
100 according to certain embodiments.
[0014] Referring to Fig. 1, the electronic device 101 in the network environment 100 may
communicate with an electronic device 102 via a first network 198 (e.g., a short-range
wireless communication network), or at least one of an electronic device 104 or a
server 108 via a second network 199 (e.g., a long-range wireless communication network).
According to an embodiment, the electronic device 101 may communicate with the electronic
device 104 via the server 108. According to an embodiment, the electronic device 101
may include a processor 120, memory 130, an input module 150, a sound output module
155, a display module 160, an audio module 170, a sensor module 176, an interface
177, a connecting terminal 178, a haptic module 179, a camera module 180, a power
management module 188, a battery 189, a communication module 190, a subscriber identification
module (SIM) 196, or an antenna module 197. In some embodiments, at least one of the
components (e.g., the connecting terminal 178) may be omitted from the electronic
device 101, or one or more other components may be added in the electronic device
101. In some embodiments, some of the components (e.g., the sensor module 176, the
camera module 180, or the antenna module 197) may be implemented as a single component
(e.g., the display module 160).
[0015] The processor 120 may execute, for example, software (e.g., a program 140) to control
at least one other component (e.g., a hardware or software component) of the electronic
device 101 coupled with the processor 120, and may perform various data processing
or computation. According to one embodiment, as at least part of the data processing
or computation, the processor 120 may store a command or data received from another
component (e.g., the sensor module 176 or the communication module 190) in volatile
memory 132, process the command or the data stored in the volatile memory 132, and
store resulting data in non-volatile memory 134. According to an embodiment, the processor
120 may include a main processor 121 (e.g., a central processing unit (CPU) or an
application processor (AP)), or an auxiliary processor 123 (e.g., a graphics processing
unit (GPU), a neural processing unit (NPU), an image signal processor (ISP), a sensor
hub processor, or a communication processor (CP)) that is operable independently from,
or in conjunction with, the main processor 121. For example, when the electronic device
101 includes the main processor 121 and the auxiliary processor 123, the auxiliary
processor 123 may be adapted to consume less power than the main processor 121, or
to be specific to a specified function. The auxiliary processor 123 may be implemented
as separate from, or as part of the main processor 121.
[0016] The auxiliary processor 123 may control at least some of functions or states related
to at least one component (e.g., the display module 160, the sensor module 176, or
the communication module 190) among the components of the electronic device 101, instead
of the main processor 121 while the main processor 121 is in an inactive (e.g., sleep)
state, or together with the main processor 121 while the main processor 121 is in
an active state (e.g., executing an application). According to an embodiment, the
auxiliary processor 123 (e.g., an image signal processor or a communication processor)
may be implemented as part of another component (e.g., the camera module 180 or the
communication module 190) functionally related to the auxiliary processor 123. According
to an embodiment, the auxiliary processor 123 (e.g., the neural processing unit) may
include a hardware structure specified for artificial intelligence model processing.
An artificial intelligence model may be generated by machine learning. Such learning
may be performed, e.g., by the electronic device 101 where the artificial intelligence
is performed or via a separate server (e.g., the server 108). Learning algorithms
may include, but are not limited to, e.g., supervised learning, unsupervised learning,
semi-supervised learning, or reinforcement learning. The artificial intelligence model
may include a plurality of artificial neural network layers. The artificial neural
network may be a deep neural network (DNN), a convolutional neural network (CNN),
a recurrent neural network (RNN), a restricted Boltzmann machine (RBM), a deep belief
network (DBN), a bidirectional recurrent deep neural network (BRDNN), deep Q-network
or a combination of two or more thereof but is not limited thereto. The artificial
intelligence model may, additionally or alternatively, include a software structure
other than the hardware structure.
[0017] The memory 130 may store various data used by at least one component (e.g., the processor
120 or the sensor module 176) of the electronic device 101. The various data may include,
for example, software (e.g., the program 140) and input data or output data for a
command related thereto. The memory 130 may include the volatile memory 132 or the
non-volatile memory 134.
[0018] The program 140 may be stored in the memory 130 as software, and may include, for
example, an operating system (OS) 142, middleware 144, or an application 146.
[0019] The input module 150 may receive a command or data to be used by another component
(e.g., the processor 120) of the electronic device 101, from the outside (e.g., a
user) of the electronic device 101. The input module 150 may include, for example,
a microphone, a mouse, a keyboard, a key (e.g., a button), or a digital pen (e.g.,
a stylus pen).
[0020] The sound output module 155 may output sound signals to the outside of the electronic
device 101. The sound output module 155 may include, for example, a speaker or a receiver.
The speaker may be used for general purposes, such as playing multimedia or playing
record. The receiver may be used for receiving incoming calls. According to an embodiment,
the receiver may be implemented as separate from, or as part of the speaker.
[0021] The display module 160 may visually provide information to the outside (e.g., a user)
of the electronic device 101. The display module 160 may include, for example, a display,
a hologram device, or a projector and control circuitry to control a corresponding
one of the display, hologram device, and projector. According to an embodiment, the
display module 160 may include a touch sensor adapted to detect a touch, or a pressure
sensor adapted to measure the intensity of force incurred by the touch.
[0022] The audio module 170 may convert a sound into an electrical signal and vice versa.
According to an embodiment, the audio module 170 may obtain the sound via the input
module 150, or output the sound via the sound output module 155 or a headphone of
an external electronic device (e.g., an electronic device 102) directly (e.g., wiredly)
or wirelessly coupled with the electronic device 101.
[0023] The sensor module 176 may detect an operational state (e.g., power or temperature)
of the electronic device 101 or an environmental state (e.g., a state of a user) external
to the electronic device 101, and then generate an electrical signal or data value
corresponding to the detected state. According to an embodiment, the sensor module
176 may include, for example, a gesture sensor, a gyro sensor, an atmospheric pressure
sensor, a magnetic sensor, an acceleration sensor, a grip sensor, a proximity sensor,
a color sensor, an infrared (IR) sensor, a biometric sensor, a temperature sensor,
a humidity sensor, or an illuminance sensor.
[0024] The interface 177 may support one or more specified protocols to be used for the
electronic device 101 to be coupled with the external electronic device (e.g., the
electronic device 102) directly (e.g., wiredly) or wirelessly. According to an embodiment,
the interface 177 may include, for example, a high definition multimedia interface
(HDMI), a universal serial bus (USB) interface, a secure digital (SD) card interface,
or an audio interface.
[0025] A connecting terminal 178 may include a connector via which the electronic device
101 may be physically connected with the external electronic device (e.g., the electronic
device 102). According to an embodiment, the connecting terminal 178 may include,
for example, a HDMI connector, a USB connector, an SD card connector, or an audio
connector (e.g., a headphone connector).
[0026] The haptic module 179 may convert an electrical signal into a mechanical stimulus
(e.g., a vibration or a movement) or electrical stimulus which may be recognized by
a user via his tactile sensation or kinesthetic sensation. According to an embodiment,
the haptic module 179 may include, for example, a motor, a piezoelectric element,
or an electric stimulator.
[0027] The camera module 180 may capture a still image or moving images. According to an
embodiment, the camera module 180 may include one or more lenses, image sensors, image
signal processors, or flashes.
[0028] The power management module 188 may manage power supplied to the electronic device
101. According to one embodiment, the power management module 188 may be implemented
as at least part of, for example, a power management integrated circuit (PMIC).
[0029] The battery 189 may supply power to at least one component of the electronic device
101. According to an embodiment, the battery 189 may include, for example, a primary
cell which is not rechargeable, a secondary cell which is rechargeable, or a fuel
cell.
[0030] The communication module 190 may support establishing a direct (e.g., wired) communication
channel or a wireless communication channel between the electronic device 101 and
the external electronic device (e.g., the electronic device 102, the electronic device
104, or the server 108) and performing communication via the established communication
channel. The communication module 190 may include one or more communication processors
that are operable independently from the processor 120 (e.g., the application processor
(AP)) and supports a direct (e.g., wired) communication or a wireless communication.
According to an embodiment, the communication module 190 may include a wireless communication
module 192 (e.g., a cellular communication module, a short-range wireless communication
module, or a global navigation satellite system (GNSS) communication module) or a
wired communication module 194 (e.g., a local area network (LAN) communication module
or a power line communication (PLC) module). A corresponding one of these communication
modules may communicate with the external electronic device via the first network
198 (e.g., a short-range communication network, such as BluetoothTM, wireless-fidelity
(Wi-Fi) direct, or infrared data association (IrDA)) or the second network 199 (e.g.,
a long-range communication network, such as a legacy cellular network, a 5th generation
(5G) network, a next-generation communication network, the Internet, or a computer
network (e.g., LAN or wide area network (WAN)). These various types of communication
modules may be implemented as a single component (e.g., a single chip), or may be
implemented as multi components (e.g., multi chips) separate from each other. The
wireless communication module 192 may identify and authenticate the electronic device
101 in a communication network, such as the first network 198 or the second network
199, using subscriber information (e.g., international mobile subscriber identity
(IMSI)) stored in the subscriber identification module 196.
[0031] The wireless communication module 192 may support a 5G network, after a 4th generation
(4G) network, and next-generation communication technology, e.g., new radio (NR) access
technology. The NR access technology may support enhanced mobile broadband (eMBB),
massive machine type communications (mMTC), or ultra-reliable and low-latency communications
(URLLC). The wireless communication module 192 may support a high-frequency band (e.g.,
the mmWave band) to achieve, e.g., a high data transmission rate. The wireless communication
module 192 may support various technologies for securing performance on a high-frequency
band, such as, e.g., beamforming, massive multiple-input and multiple-output (massive
MIMO), full dimensional MIMO (FD-MIMO), array antenna, analog beam-forming, or large
scale antenna. The wireless communication module 192 may support various requirements
specified in the electronic device 101, an external electronic device (e.g., the electronic
device 104), or a network system (e.g., the second network 199). According to an embodiment,
the wireless communication module 192 may support a peak data rate (e.g., 20Gbps or
more) for implementing eMBB, loss coverage (e.g., 164dB or less) for implementing
mMTC, or U-plane latency (e.g., 0.5ms or less for each of downlink (DL) and uplink
(UL), or a round trip of 1ms or less) for implementing URLLC.
[0032] The antenna module 197 may transmit or receive a signal or power to or from the outside
(e.g., the external electronic device) of the electronic device 101. According to
an embodiment, the antenna module 197 may include an antenna including a radiating
element composed of a conductive material or a conductive pattern formed in or on
a substrate (e.g., a printed circuit board (PCB)). According to an embodiment, the
antenna module 197 may include a plurality of antennas (e.g., array antennas). In
such a case, at least one antenna appropriate for a communication scheme used in the
communication network, such as the first network 198 or the second network 199, may
be selected, for example, by the communication module 190 (e.g., the wireless communication
module 192) from the plurality of antennas. The signal or the power may then be transmitted
or received between the communication module 190 and the external electronic device
via the selected at least one antenna. According to an embodiment, another component
(e.g., a radio frequency integrated circuit (RFIC)) other than the radiating element
may be additionally formed as part of the antenna module 197.
[0033] According to certain embodiments, the antenna module 197 may form a mmWave antenna
module. According to an embodiment, the mmWave antenna module may include a printed
circuit board, an RFIC disposed on a first surface (e.g., the bottom surface) of the
PCB, or adjacent to the first surface and capable of supporting a designated high-frequency
band (e.g., the mmWave band), and a plurality of antennas (e.g., array antennas) disposed
on a second surface (e.g., the top or a side surface) of the PCB, or adjacent to the
second surface and capable of transmitting or receiving signals of the designated
high-frequency band.
[0034] At least some of the above-described components may be coupled mutually and communicate
signals (e.g., commands or data) therebetween via an inter-peripheral communication
scheme (e.g., a bus, general purpose input and output (GPIO), serial peripheral interface
(SPI), or mobile industry processor interface (MIPI)).
[0035] According to an embodiment, commands or data may be transmitted or received between
the electronic device 101 and the external electronic device 104 via the server 108
coupled with the second network 199. Each of the electronic devices 102 or 104 may
be a device of a same type as, or a different type, from the electronic device 101.
According to an embodiment, all or some of operations to be executed at the electronic
device 101 may be executed at one or more of the external electronic devices 102,
104, or 108. For example, if the electronic device 101 should perform a function or
a service automatically, or in response to a request from a user or another device,
the electronic device 101, instead of, or in addition to, executing the function or
the service, may request the one or more external electronic devices to perform at
least part of the function or the service. The one or more external electronic devices
receiving the request may perform the at least part of the function or the service
requested, or an additional function or an additional service related to the request,
and transfer an outcome of the performing to the electronic device 101. The electronic
device 101 may provide the outcome, with or without further processing of the outcome,
as at least part of a reply to the request. To that end, a cloud computing, distributed
computing, mobile edge computing (MEC), or client-server computing technology may
be used, for example. The electronic device 101 may provide ultra low-latency services
using, e.g., distributed computing or mobile edge computing. In another embodiment,
the external electronic device 104 may include an Internet-of things (IoT) device.
The server 108 may be an intelligent server using machine learning and/or a neural
network. According to an embodiment, the external electronic device 104 or the server
108 may be included in the second network 199. The electronic device 101 may be applied
to intelligent services (e.g., smart home, smart city, smart car, or healthcare) based
on 5G communication technology or IoT-related technology.
[0036] The electronic device according to certain embodiments may be one of various types
of electronic devices. The electronic devices may include, for example, a portable
communication device (e.g., a smart phone), a computer device, a portable multimedia
device, a portable medical device, a camera, a wearable device, or a home appliance.
According to an embodiment of the disclosure, the electronic devices are not limited
to those described above.
[0037] It should be appreciated that certain embodiments of the present disclosure and the
terms used therein are not intended to limit the technological features set forth
herein to particular embodiments and include various changes, equivalents, or replacements
for a corresponding embodiment. With regard to the description of the drawings, similar
reference numerals may be used to refer to similar or related elements. It is to be
understood that a singular form of a noun corresponding to an item may include one
or more of the things, unless the relevant context clearly indicates otherwise. As
used herein, each of such phrases as "A or B," "at least one of A and B," "at least
one of A or B," "A, B, or C," "at least one of A, B, and C," and "at least one of
A, B, or C," may include all possible combinations of the items enumerated together
in a corresponding one of the phrases. As used herein, such terms as "1st" and "2nd,"
or "first" and "second" may be used to simply distinguish a corresponding component
from another, and does not limit the components in other aspect (e.g., importance
or order). It is to be understood that if an element (e.g., a first element) is referred
to, with or without the term "operatively" or "communicatively", as "coupled with,"
"coupled to," "connected with," or "connected to" another element (e.g., a second
element), it means that the element may be coupled with the other element directly
(e.g., wiredly), wirelessly, or via a third element.
[0038] As used herein, the term "module" may include a unit implemented in hardware, software,
or firmware, and may interchangeably be used with other terms, for example, "logic,"
"logic block," "part," or "circuitry". A module may be a single integral component,
or a minimum unit or part thereof, adapted to perform one or more functions. For example,
according to an embodiment, the module may be implemented in a form of an application-specific
integrated circuit (ASIC).
[0039] Certain embodiments as set forth herein may be implemented as software (e.g., the
program 140) including one or more instructions that are stored in a storage medium
(e.g., internal memory 136 or external memory 138) that is readable by a machine (e.g.,
the electronic device 101). For example, a processor (e.g., the processor 120) of
the machine (e.g., the electronic device 101) may invoke at least one of the one or
more instructions stored in the storage medium, and execute it, with or without using
one or more other components under the control of the processor. This allows the machine
to be operated to perform at least one function according to the at least one instruction
invoked. The one or more instructions may include a code generated by a complier or
a code executable by an interpreter. The machine-readable storage medium may be provided
in the form of a non-transitory storage medium. Wherein, the term "non-transitory"
simply means that the storage medium is a tangible device, and does not include a
signal (e.g., an electromagnetic wave), but this term does not differentiate between
where data is semi-permanently stored in the storage medium and where the data is
temporarily stored in the storage medium.
[0040] According to an embodiment, a method according to certain embodiments of the disclosure
may be included and provided in a computer program product. The computer program product
may be traded as a product between a seller and a buyer. The computer program product
may be distributed in the form of a machine-readable storage medium (e.g., compact
disc read only memory (CD-ROM)), or be distributed (e.g., downloaded or uploaded)
online via an application store (e.g., PlayStoreTM), or between two user devices (e.g.,
smart phones) directly. If distributed online, at least part of the computer program
product may be temporarily generated or at least temporarily stored in the machine-readable
storage medium, such as memory of the manufacturer's server, a server of the application
store, or a relay server.
[0041] According to certain embodiments, each component (e.g., a module or a program) of
the above-described components may include a single entity or multiple entities, and
some of the multiple entities may be separately disposed in different components.
According to certain embodiments, one or more of the above-described components may
be omitted, or one or more other components may be added. Alternatively or additionally,
a plurality of components (e.g., modules or programs) may be integrated into a single
component. In such a case, according to certain embodiments, the integrated component
may still perform one or more functions of each of the plurality of components in
the same or similar manner as they are performed by a corresponding one of the plurality
of components before the integration. According to certain embodiments, operations
performed by the module, the program, or another component may be carried out sequentially,
in parallel, repeatedly, or heuristically, or one or more of the operations may be
executed in a different order or omitted, or one or more other operations may be added.
[0042] FIGS. 2A and 2B are perspective views of an electronic device according to various
embodiments. FIG. 2A is a perspective view of the front surface of the electronic
device 101 in FIG. 1 according to various embodiments, and FIG. 2B is a perspective
view of the rear surface of the electronic device 101 in FIG. 1.
[0043] Referring to FIGS. 2A and 2B, an electronic device (e.g., the electronic device 101
in FIG. 1) according to various embodiments may include a housing 210 which includes
a first surface (or a front surface) 210A, a second surface (or a rear surface) 210B,
and a side surface 210C surrounding the space between the first surface 210A and the
second surface 210B. According to another embodiment, the housing 210 may be a structure
forming some of the first surface 210A, the second surface 210B, and the side surface
210C. According to an embodiment, the first surface 210A may be formed of a front
plate, at least a part of which is substantially transparent (e.g., a polymer plate,
or a glass plate including various coated layers). The second surface 210B may be
formed of a substantially opaque rear plate. The rear plate may be formed of, for
example, coated or colored glass, ceramic, polymer, metal (e.g., aluminum, stainless
steel (STS), or magnesium), or a combination of at least two of the materials. The
side surface 210C may be coupled to the front plate and the rear plate, and may be
formed of a side bezel structure 218 (or "a side member") containing metal and/or
polymer. In an embodiment, the rear plate and the side bezel structure 218 may be
integrally formed, and may contain an identical material (e.g., a metal material such
as aluminum).
[0044] According to various embodiments, the front plate may include a first area 210D,
curved and seamlessly extending from the first surface 210A toward the rear plate,
at both ends of a long edge of the front plate. Alternatively, the rear plate may
include a second area 210E, curved and seamlessly extending from the second surface
210B toward the front plate, at both ends of a long edge thereof. In an embodiment,
the front plate or the rear plate may include only one of the first area 210D or the
second area 210E. In an embodiment, the front plate may include only a flat surface
disposed parallel to the second surface 210B without including the first area 210D
and the second area 210E. When the electronic device 101 is seen from the side, the
side bezel structure 218 may have a first thickness (or width) at the side surface
which does not include the first area 210D or the second area 210E, described above,
and may have a second thickness less than the first thickness at the side surface
which includes the first area 210D or the second area 210E.
[0045] A display 230 (e.g., the display module 160 in FIG. 1) may be exposed through a considerable
part of the front plate. In an embodiment, at least a part of the display 230 may
be exposed through the front plate which forms the first surface 210A and the first
area 210D. The display 230 may be coupled to or disposed adjacent to a touch sensing
circuit, a pressure sensor capable of measuring the strength (pressure) of a touch,
and/or a digitizer for detecting a magnetic field-type stylus pen. In an embodiment,
at least some of sensor modules 204 and 207 (e.g., the sensor module 176 in FIG. 1)
and/or at least some of input modules (e.g., the input module 150 in FIG. 1) may be
disposed in the first area 210D and/or the second area 210E.
[0046] The sensor modules 204 and 207 may generate electrical signals or data values corresponding
to an operation state inside the electronic device 101 or an environment state outside
the electronic device 101. The sensor modules 204 and 207 may include, for example,
a first sensor module (e.g., a proximity sensor) and/or a second sensor module (e.g.,
a fingerprint sensor), disposed in the first surface 210A of the housing 210, and/or
a third sensor module (e.g., an HRM sensor) disposed in the second surface 210B of
the housing 210. The fingerprint sensor may be disposed in a partial area of the first
surface 210A (e.g., a home key button) of the housing 210 or a partial area of the
second surface 210B, and/or under the display 230.
[0047] Camera modules 250 and 255 (e.g., the camera module 180 in FIG. 1) may include a
first camera module 250 disposed in the first surface 210A of the electronic device
101, a second camera module 255 disposed in the second surface 210B, and/or a flash
213. The camera modules 250 and 255 may include one lens or multiple lenses, an image
sensor, and/or an image signal processor. The flash 213 may include a light-emitting
diode or a xenon lamp. In an embodiment, at least two lenses (a wide-angle lens, an
ultra-wide-angle lens, or a telephoto lens) and image sensors may be disposed in one
surface of the electronic device 101.
[0048] The first camera module 250, some sensor modules 204, or an indicator may be disposed
to be exposed through the display 230. For example, the first camera module 250, the
sensor module 204, or the indicator may be disposed in the inner space of the electronic
device 101 so as to be brought into contact with an external environment through an
opening of the display 230, bored up to the front plate, or a transmissive area thereof.
According to an embodiment, an area in which the display 230 faces the first camera
module 250 is an area in which contents are displayed, and may be formed as a transmissive
area having predetermined transmissivity. According to an embodiment, the transmissive
area may be formed to have transmissivity ranging from about 5% to about 20%. This
transmissive area may include an area overlapping an effective area (e.g., a field-of-view
area) of the first camera module 250, through which light that is imaged by an image
sensor to producing an image passes. For example, the transmissive area of the display
230 may include an area having a pixel density lower than that therearound. For example,
the transmissive area may replace the opening. For example, the first camera module
250 may include an under-display camera (UDC). In another embodiment, some sensor
modules 204 may be disposed so as to perform functions thereof without being visually
exposed through the front plate in the inner space of the electronic device. For example,
in this case, an area of the display 230, which faces the sensor module, may not require
a bored opening.
[0049] According to various embodiments, the electronic device 101 has a bar-type or plate-type
exterior, but the disclosure is not limited thereto. For example, the electronic device
101 may be a part of a foldable electronic device, a slidable electronic device, a
stretchable electronic device, and/or a rollable electronic device. The "foldable
electronic device", the "slidable electronic device", the "stretchable electronic
device", and/or the "rollable electronic device" may imply an electronic device wherein,
because the bending deformation of the display 230 is possible, at least a part of
the electronic device can be folded or wound (or rolled), or the area of the electronic
device can be at least partially enlarged and/or received into the housing 210. In
the foldable electronic device, the slidable electronic device, the stretchable electronic
device, and/or a rollable electronic device, a screen display area may be extended
and used by unfolding a display or exposing the wider area of the display according
to a user's need .
[0050] FIG. 3 is a partial cross-sectional view of an electronic device, taken along line
5-5 in FIG. 2A according to various embodiments.
[0051] In describing FIG. 3, the description is made while providing an unbreakable (UB)
type OLED display (e.g., curved display) as an example, but is not limited thereto.
For example, the description may also be applied to a flat type display of on-cell
touch Active Matrix Organic Light-Emitting Diode (AMOLED) (OCTA) scheme.
[0052] Referring to FIG. 3, an electronic device 300 may include a front cover 320 (e.g.,
a cover member, a front plate, a front window, or a first plate) facing a first direction
(the z-axis direction), a rear cover 380 (e.g., a rear cover member, a rear plate,
a rear window, or a second plate) facing a direction opposite to the direction faced
by the front cover 320, and a side member 310 surrounding a space 3001 between the
front cover 320 and the rear cover 380. According to an embodiment, the electronic
device 300 may include a first waterproof member 3201 disposed between a subsidiary
material layer 440 of a display 400 and the side member 310. According to an embodiment,
the electronic device 300 may include a second waterproof member 3801 disposed between
the side member 310 and the rear plate 380. The first waterproof member 3201 and the
second waterproof member 3801 may prevent outside foreign matter or water from flowing
into the inner space 3001 of the electronic device 300. In another embodiment, a waterproof
member may be disposed in at least a part of a mounting support structure between
a camera module 500 and the side member 310. In another embodiment, the first waterproof
member 3201 and/or the second waterproof member 3801 may be replaced with an adhesive
member.
[0053] According to various embodiments, the side member 310 may further include a first
support member 311 which at least partially extends into the inner space 3001 of the
electronic device 300. According to an embodiment, the first support member 311 may
be formed by a structural coupling with the side member 310. According to an embodiment,
the first support member 311 may support the camera module 500 such that the camera
module 500 is aligned and disposed near the rear surface of a display panel 431 through
an opening (e.g., an opening (OP) in FIG. 4) of the subsidiary material layer 440
of the display 400.
[0054] According to various embodiments, the camera module 500 may include a camera housing
510, a lens housing 520 disposed in an inner space 5101 of the camera housing 510
and at least partially protruding in a display direction (e.g., the z-axis direction),
multiple lenses 530 (531, 532, 533, and 534) aligned at regular intervals in an inner
space 5201 of the lens housing 520, and at least one image sensor 540 disposed in
the inner space 5101 of the camera housing 510 so as to acquire at least a part of
light having passed through the multiple lenses 530. According to an embodiment, when
the camera module 500 includes an auto focus (AF) function), the lens housing 520
may move through a predetermined driver in the camera housing 510 such that the distance
to the display panel 431 varies.
[0055] According to an embodiment, a separate driver may be disposed such that the camera
module 500 changes the position of at least one of the multiple lenses 530 in order
to perform the AF function. In another embodiment, in the camera module 500, the camera
housing 510 may be omitted, and the lens housing 520 may be directly disposed at the
first support member 311 through a predetermined alignment process. According to an
embodiment, when the lens housing 520 is directly disposed at the first support member
311, in order to reduce a camera arrangement space, the camera housing 510 may be
omitted and the lens housing 520 may be disposed to be attached to one side surface
of the first support member 311. According to an embodiment, the camera module 500
may be aligned through a through-hole 301 of the first support member 311, and then
may be attached to the rear surface of the first support member 311 by an adhesive
member 312 (e.g., a bonding member or a tape member).
[0056] FIG. 4 is an enlarged cross-sectional view of an area including a camera module of
an electronic device according to various embodiments. For example, FIG. 4 is an enlarged
view of an area 6 including the camera module in FIG. 3.
[0057] Referring to FIG. 4, the electronic device 300 may include an adhesive layer 410,
a polarizer (POL) 432, the display panel 431, and the subsidiary material layer 440,
which are disposed between the rear surface of the front cover 320 and the side member
310. According to an embodiment, when the front plate 320 is seen from above, the
POL 432 may include an opening 4321 formed in order to improve optical transmissivity
of the camera module 500. In another embodiment, in the adhesive member (or the adhesive
layer) 410 disposed on the POL 432, a part corresponding to the opening 4321 may be
at least partially omitted. That is, the adhesive member (or the adhesive layer) 410
may have an opening corresponding to the opening 4321. In an embodiment, the opening
4321 formed in the POL 432 may be filled with an index material for adjusting the
refractive index according to an increase in interface reflection.
[0058] According to an embodiment, an area of the POL 432 corresponding to the multiple
lenses 530 may be formed to have high transmissivity without having the opening 4321
formed therethrough. For example, at least a partial area of the POL 432 (e.g., an
area corresponding to the multiple lenses 530) may be formed of a material having
transmissivity different from that of the remaining area of the POL 432, or may be
formed of another member capable of increasing transmissivity. According to an embodiment,
a member (not shown) for increasing transmissivity may be disposed on at least a part
(e.g., an upper side surface or a lower side surface) of the area of the POL 432 corresponding
to the multiple lenses 530. According to an embodiment, when the front cover 320 is
seen from above (e.g., in the +z-axis direction), the subsidiary material layer 440
may include an opening (OP) formed in an area at least partially overlapping the multiple
lenses 530. According to an embodiment, the opening (OP) formed in the subsidiary
material layer 440 may be formed as one opening (OP) by overlapping an opening formed
in a light-blocking layer 441, an opening formed in a cushion layer 442, an opening
formed in a functional member 443, and an opening formed in a conductive member 444.
According to an embodiment, the openings may have different sizes in response to the
shape of the camera module 500.
[0059] According to various embodiments, when the display 400 is seen from above (e.g.,
the +z-axis direction), the display panel 431 may include a first area A1, which overlaps
the field of view (0) of the camera module 500, and a second area A2 surrounding the
first area A1. According to an embodiment, the first area A1 may be formed to have
light transmissivity required by the camera module 500 through adjustment of a pixel
density and/or a wiring density. According to an embodiment, the second area A2 may
include a normal active area of the display panel 431. According to an embodiment,
the second area A2 may be an area in which light transmissivity for the camera module
500 has not been taken into account. According to an embodiment, the display panel
431 may include first multiple pixels, arranged to have a first arrangement density
in the first area A1, and second multiple pixels having a second arrangement density
higher than the first arrangement density in the second area A2. In an embodiment,
the wiring density of the first area A1 may be formed to be lower than the wiring
density of the second area A2, thereby contributing to transmissivity improvement.
[0060] According to various embodiments, the first area A1 of the display panel 431 has
a lower pixel density than the second area A2 therearound, and thus a light-transmitting
area, which does not emit light, between a pixel and a pixel may be recognized as
black and may be viewed from the outside. The display panel 431 according to exemplary
embodiments of the disclosure may include a light extractor for guiding at least a
part of light generated through pixels so as to be totally reflected to an optical
waveguide layer and emitted to the outside through the light-transmitting area, and
thus the above problems may be solved.
[0061] FIG. 5 illustrates an example in which a camera and at least one light source are
disposed in an electronic device according to various embodiments. FIG. 5 illustrates
the state of the front surface (e.g., a surface on which a display is exposed) of
an electronic device seen by a user while the electronic device stands up.
[0062] Referring to FIG. 5, an electronic device (e.g., the electronic device 101 in FIG.
1) according to various embodiments may include a camera 525 (e.g., the camera module
180 in FIG. 1 or the camera modules 250 and 255 in FIGS. 2A and 2B) under a display
(e.g., the display module 160 in FIG. 1 or the display 230 in FIGS. 2A and 2B) (e.g.,
the -z-axis direction in FIG. 2A). The display 230 is an area in which information
about the electronic device 101 is displayed, and may be implemented as, for example,
an OLED. The camera 525 may include a filter 515 (e.g., IR band pass filter), an image
sensor, or at least one light source (e.g., a first light source 561 and a second
light source 563). The camera 525 may output light through the at least one light
source, the output light reflected by an object (e.g., a subject, a person, or a thing)
may be sensed by filter 515, and an image having a designated wavelength may be captured
by the image sensor. When the image sensor is close to the light source, a red-eye
effect occurs. When the image sensor is far from the light source, the amount of light
may be reduced or light uniformity may be caused.
[0063] A pupil (pupil of an eye) of a person may be reduced in a bright environment to decrease
the amount of light and may be enlarged in a dark environment to receive a large amount
of light, thereby automatically adjusting the amount of light reaching the retina
depending on brightness and darkness. When an image of the face of a person is captured
using a flash in a dark environment, a dark-adapted pupil is already enlarged, and
thus when light from the flash reaches the retina, the light may be reflected in capillaries
behind the retina. The reflected light comes out of an eye again. At this time, the
photographed pupil of the person appears red, not original black, and this effect
may be called a red-eye effect.
[0064] The camera 525 may be designed such that the image sensor and the at least one light
source are positioned while being spaced a predetermined distance apart from each
other. IR LEDs may be used as the first light source 561 and the second light source
563, and a lens 570 may be inserted in front of the light source such that a predetermined
area is irradiated with light. The first light source 561 may be disposed at a first
distance from the camera 525, and the second light source 563 may be disposed at a
second distance from the camera 525. The first distance may be shorter than the second
distance. For example, the first distance may be within about 10 mm. A first power
controller 545 may adjust the intensity of the first light source 561, and a second
power controller 550 may adjust the intensity of the second light source 563. The
first power controller 545 or the second power controller 550 may adjust the amount
of light according to the transmissivity of the display 230. An analyzer 535 may analyze
an image transmitted from the image sensor, and may determine whether an object in
the image is a real person (e.g., live, true) or an imitation (e.g., fake, false)
such as paper or a sham. The analyzer 535 may control, based on the determination
result, the first power controller 545 or the second power controller 550 to randomly
drive the first light source 561 or the second light source 563. The first light source
561 may be disposed at a distance (e.g., within about 10 mm) close to the camera 525,
at which a red-eye effect occurs, and the second light source 563 may be disposed
at a distance (e.g., about 25 mm to 50 mm) at which the red-eye effect does not occur.
The drawing illustrates that two light sources are included, but the number of light
sources may be smaller or greater than two. The first power controller 545, the second
power controller 550 or the analyzer 535 may operate under control of a processor
(e.g., the processor 120 in FIG. 1). The drawing illustrates that a separate light
source is included, but a light source included in the display 230 may be used as
the light source.
[0065] An electronic device (e.g., the electronic device 101 in FIG. 1) according to various
embodiments may include a display (e.g., the display module 160 in FIG. 1 or the display
230 in FIGS. 2A and 2B), a camera module (e.g., the camera module 180 in FIG. 1 or
the camera modules 250 and 255 in FIGS. 2A and 2B) disposed under the display, at
least one light source (e.g., a first light source 821 to a fifth light source 829
in FIGS. 8A and 8B or a first light source 921 to a fourth light source 927 in FIGS.
9A and 9B) disposed to correspond to the camera module, a memory (e.g., the memory
130 in FIG. 1), and a processor (e.g., the processor 120 in FIG. 1) operatively connected
to at least one among the display, the camera module, the light source, or the memory,
wherein the processor is configured to drive the camera module and the at least one
light source in response to a request for biometric authentication, acquire a face
image from the camera module, analyze the face image, based on the driven at least
one light source, and perform biometric authentication based on the analysis result.
[0066] The at least one light source may include a first light source (e.g., a fifth light
source 829 in FIGS. 8A and 8B, or a third light source 925 in FIGS. 9A and 9B) disposed
at a first distance from the camera module and a second light source (e.g., a first
light source 821 to a fourth light source 827 in FIGS. 8A and 8B, or a first light
source 921, a second light source 923, and a fourth light source 927 in FIGS. 9A and
9B) disposed at a second distance from the camera module, and the first distance may
be configured to be shorter than the second distance.
[0067] The processor may be configured to determine whether a red-eye effect is detected
from an eye included in the face image when the first light source is driven, and
determine whether a specular highlight is detected from the eye included in the face
image when the second light source is driven.
[0068] The processor may be configured to determine whether the size of a reflected ray
detected from the eye appears larger than a predetermined reference value when the
first light source is driven, determine biometric verification to be successful when
the size of the reflected ray is larger than the predetermined value, and determine
biometric verification to be unsuccessful when the reflected ray is not detected from
the eye or when the size of the reflected ray is smaller than the determined reference
value.
[0069] The processor may be configured to determine whether the size of a reflected light
detected from the eye appears smaller than a predetermined reference value when the
second light source is driven, determine biometric verification to be successful when
the size of the reflected ray is smaller than the predetermined reference value, and
determine biometric verification to be unsuccessful when the reflected ray is not
detected from the eye or when the size of the reflected ray is larger than the predetermined
reference value.
[0070] The electronic device may further include a third light source (e.g., a first light
source 821 to a fourth light source 827 in FIGS. 8A and 8B, or a first light source
921, a second light source 923, and a fourth light source 927 in FIGS. 9A and 9B)
disposed at the second distance from the camera module, and the processor may be configured
to drive one of the second light source or the third light source to acquire a first
face image, determine whether the number of reflected rays detected from an eye included
in the first face image is one, drive, when the number of reflected rays detected
from the eye included in the first face image is one, the second light source and
the third light source to acquire a second face image, determine whether the number
of reflected rays detected from an eye included in the second face image is two, determine
biometric verification to be successful when the number of reflected rays detected
from the eye included in the second face image is two, and determine biometric verification
to be unsuccessful when the reflected rays are not detected from the eye or when more
or less than two reflected rays are detected.
[0071] The at least one light source may be configured to be an infrared ray (IR) light-emitting
diode (LED).
[0072] The biometric authentication may include biometric authentication of determining
whether the acquired face image corresponds to a face image stored in the memory and
an operation of determining biometric liveness, based on the driven light source.
[0073] The processor may be configured to perform a function related to requested biometric
authentication when the number of reflected rays detected from an eye included in
the face image corresponds to the number of the driven light sources and when the
acquired face image corresponds to the face image stored in the memory.
[0074] The processor may be configured to determine, based on the security level of the
requested biometric authentication, the number of times biometric liveness is determined
based on the driven light source.
[0075] FIG. 6 is a flowchart 600 illustrating a method for operating an electronic device
according to various embodiments.
[0076] Referring to FIG. 6, in operation 601, a processor (e.g., the processor 120 in FIG.
1) of an electronic device (e.g., the electronic device 101 in FIG. 1) according to
various embodiments may be requested to perform biometric authentication. The biometric
authentication may be extracting and authenticating various types of biometric information
acquirable from a user, such as a fingerprint, an iris, a face, a voice, or a vein
of the back of a hand. The biometric authentication may be requested for unlocking
of the electronic device 101, a financial transaction service or a payment service,
or application configuration.
[0077] In operation 603, the processor 120 may drive a camera (e.g., the camera module 180
in FIG. 1 or the camera modules 250 and 255 in FIGS. 2A and 2B) and a light source
(e.g., the first light source 561 and the second light source 563 in FIG. 5). The
camera module 180 may include an under-display camera (UDC) disposed under (e.g.,
the-z-axis direction in FIG. 3) a display (e.g., the display module 160 in FIG. 1).
For example, for biometric authentication, the processor 120 may drive the camera
module 250 disposed in the front surface of the electronic device 101. Further, the
processor 120 may drive a light source in order to determine biometric liveness together
with biometric authentication. The light source may be disposed to be positioned at
a predetermined distance from the camera module 180. For example, the first light
source 561 and the second light source 563 may be disposed under the display module
160, and IR LEDs may be used. If an IR LED is used as a light source, the user may
not identify that a light source is driven even when the light source is driven. The
electronic device 101 may include at least one light source. When multiple light sources
are included, the processor 120 may drive at least one light source among the multiple
light sources. According to various embodiments, a light source included in the display
module 160 may be used as a light source to be driven.
[0078] In operation 605, the processor 120 may acquire a face image from the camera. The
face image includes the user's face, and may include only a partial area of the user's
face according to an embodiment. For example, the face image may include the entire
face of the user, or a part of the face. For example, when the user's face, apart
from biometric liveness, is used for biometric recognition, the processor 120 may
acquire the entirety of the user's face as a face image. Alternatively, when the user's
iris is used for biometric authentication, the processor 120 may acquire an image
including the user's eye as a face image.
[0079] In operation 607, the processor 120 may analyze the face image, based on the driven
light source. When one light source is driven, the processor 120 may analyze whether
a reflected ray is included in an eye of the face image. A reflected ray included
in the eye may imply a ray which has been emitted from a light source and reflected
by the user's eye. The reflected ray may include a specular highlight or a red-eye
effect. Even in an IR source in addition to a visible ray, a highlight due to reflection
may be appear in a captured eye image, and the specular highlight may vary depending
on the angle between the light source and the camera and the number of light sources.
The specular highlight may not be detected in a photograph or paper on which a face
is printed, and biometric liveness may be detected by analyzing an eye image captured
while changing the number and position of light sources.
[0080] Further, the red-eye effect may refer to an effect by which a pupil part of a person
appears red when capturing an image of the person using a flash in a dark environment.
The red-eye effect and the specular highlight may be different from each other in
at least one of size, color, or form. For example, the size of a reflected ray in
which the red-eye effect occurs may be larger than the size of a reflected ray in
which the specular highlight appears.
[0081] According to various embodiments, when the distance between a camera (e.g., an image
sensor) and a light source decreases, a red-eye effect may occur, and thus the size
of a reflected ray (e.g., the red-eye effect) is large. When the distance between
the camera and the light source increases, the size of a reflected ray (e.g., a specular
highlight) may be small. The processor 120 may recognize a face from the acquired
face image and detect an eye, based on the face recognition, to perform an operation
for biometric liveness determination. Alternatively, the processor 120 may detect
an eye from the face image to perform an operation for biometric liveness determination.
[0082] For example, the electronic device may include two light sources. A first light source
may be disposed at a close distance (e.g., a first distance) to the camera, and a
second light source may be disposed at a relatively far distance (e.g., a second distance)
from the camera compared with the first light source. A reflected ray included in
an eye of a face image acquired after driving the first light source corresponds to
a red-eye effect, and thus may appear larger than when the second light source is
driven. When the size of a reflected ray included in the eye of the face image acquired
after driving the first light source appears larger than a predetermined reference
value, the processor 120 may determine that biometric verification is successful (e.g.,
live, true). When the size of a reflected ray appears smaller than the predetermined
reference value, the processor 120 may determine that biometric verification is unsuccessful
(e.g., fake, false). Alternatively, when the size of a reflected ray included in an
eye of a face image after driving the second light source appears smaller than the
predetermined reference value, the processor 120 may determine that biometric verification
is successful (e.g., live, true), and when the size of a reflected ray included in
the eye appears larger than the predetermined reference value, the processor 120 may
determine that biometric verification is unsuccessful (e.g., fake, false).
[0083] According to various embodiments, three light sources may be included in the electronic
device, a first light source may be disposed close to the camera, and a second light
source and a third light source may be disposed at a relatively far distance from
the camera compared with the first light source. One reflected ray included in an
eye of a face image acquired after driving the second light source may be detected,
and two reflected rays included in an eye of a face image acquired after driving the
second light source and the third light source may be detected. When the number of
reflected rays included in an eye of a face image corresponds to (e.g., is equal to)
the number of driven light sources, the processor 120 may determine that biometric
verification is successful (e.g., live, true). When the number of reflected rays included
in an eye of a face image does not correspond to the number of driven light sources,
the processor 120 may determine that biometric verification is unsuccessful (e.g.,
fake, false).
[0084] In operation 609, the processor 120 may perform biometric authentication based on
the analysis result. The biometric authentication may include biometric authentication
and biometric liveness determination. The biometric authentication may be determining
whether a living body corresponds to biometric information (e.g., a face, a fingerprint,
or an iris) of a user, stored in a memory (e.g., the memory 130 in FIG. 1), and the
biometric liveness determination may be determining, based on a light source, whether
the living body corresponds to a real person which is not paper or an imitation. The
processor 120 may determine, based on the analysis result, biometric authentication
and biometric liveness. When biometric authentication and biometric liveness determination
are successful, the processor 120 may allow a function corresponding to the biometric
authentication requested in operation 601. When biometric authentication and biometric
liveness determination are unsuccessful, the processor 120 may not allow the function
corresponding to the biometric authentication requested in operation 601.
[0085] According to various embodiments, a face image may be acquired for biometric liveness
determination. When biometric authentication using a face image is possible, the processor
120 may perform biometric authentication by using the face image acquired in operation
605. Alternatively, when biometric authentication using a face image is impossible
(e.g., fingerprint authentication), the processor 120 may further request biometric
information for biometric authentication.
[0086] According to various embodiments, the processor 120 may differently determine biometric
liveness, based on the security level (or type) of the biometric authentication requested
in operation 601. For example, when biometric authentication is requested in relation
to a financial transaction or a payment service, the processor 120 may determine biometric
liveness for determining both a red-eye effect and a specular highlight (e.g., determination
of the number of reflected rays) for security improvement. Alternatively, when biometric
authentication is requested in relation to unlocking the electronic device 101, the
processor 120 may perform biometric liveness determination for determining only a
red-eye effect or determining only a specular highlight (e.g., the number of reflected
rays). The security level of biometric authentication may be configured in an application,
may be configured by a user, or may be configured in the electronic device 101.
[0087] FIG. 7 illustrates an example in which a reflected ray is detected from a user's
eye by a light source according to various embodiments.
[0088] Referring to FIG. 7, a processor (e.g., the processor 120 in FIG. 1) of an electronic
device (e.g., the electronic device 101 in FIG. 1) according to various embodiments
may acquire an eye image 710 from a camera 735 (e.g., the camera module 180 in FIG.
1, or the camera modules 250 and 255 in FIGS. 2A and 2B). The electronic device 101
may include at least one light source 737 closed (or adjacent) (e.g., a first distance)
to the camera 735 or at a predetermined distance (a certain distance) (e.g., a second
distance) therefrom. Referring to figure sign 750, light emitted from the light source
737 is reflected by two eyes 731 and 733 of a user, and thus a reflected ray 705 may
appear. Referring to the eye image 710, the reflected ray 705 may appear in a cornea
701 so as to be adj acent to a pupil 703. The reflected ray 705, which is a concept
including a specular highlight or a red-eye effect, and, in FIG. 7, may be an illustration
of the specular highlight. When a light source disposed close (or adjacent) to the
camera 735 is driven, a red-eye effect may occur, and when a light source disposed
at the predetermined distance (e.g., the second distance) from the camera 735 is driven,
a specular highlight may appear. For example, the size of a reflected ray in which
the red-eye effect has occurred may be larger than the size of a reflected ray in
which the specular highlight has appeared.
[0089] FIGS. 8A and 8B illustrate an example of authenticating biometric liveness by randomly
driving a light source in an electronic device according to various embodiments.
[0090] Referring to FIG. 8A, an electronic device (e.g., the electronic device 101 in FIG.
1) according to various embodiments may include a camera 801 (e.g., the camera module
180 in FIG. 1, or the camera modules 250 and 255 in FIGS. 2A and 2B) and at least
one light source 821, 823, 825, 827, or 829 (e.g., the first light source 561 and
the second light source 563 in FIG. 5). The camera 801 may include an under-display
camera (UDC) disposed under a display (e.g., the display module 160 in FIG. 1). A
first light source 821, a second light source 823, a third light source 825, and a
fourth light source 827 may be disposed at a predetermined distance (e.g., a second
distance) from the camera 801, and a fifth light source 829 may be disposed at a relatively
close distance (e.g., a first distance) to the camera 801, compared with the first
light source 821 to the fourth light source 827. The first distance may be shorter
than the second distance. The first light source 821 to the fifth light source 829
may be disposed under the display module 160, and IR LEDs may be used therefor.
[0091] According to various embodiments, the camera 801 may be disposed at the center of
the electronic device 101 corresponding to the long length of two parallel side surfaces
of the electronic device 101, and the at least one light source 821, 823, 825, 827,
or 829 may be disposed about the camera 801. In the drawing, it is illustrated that
distances by which the first light source 821 to the fourth light source 827 are spaced
apart from the camera 801 are equal or similar to each other. However, the distances
by which the first light source 821 to the fourth light source 827 are spaced apart
from the camera 801 may be different from each other. A first embodiment 810 to a
fifth embodiment 890 show the front view of the electronic device 101, and a cross-sectional
view 813 is a cross-sectional view of the electronic device 101, taken along line
A. Eye images described below may imply face images. An eye image may be acquired
as a face image, or an eye image may be enlarged (or extracted) from in a face image.
[0092] The first embodiment 810 shows an example in which the fifth light source 829 is
driven. When the fifth light source 829 is driven, the size of a first reflected ray
803 (e.g., a red-eye effect) in an acquired first eye image 815 may appear relatively
large. The fifth light source 829 is disposed at the first distance from the camera
801. When the distance between the camera 801 and the fifth light source 829 is shorter,
the size of the first reflected ray 803 may be relative large due to a red-eye effect.
When the size of the first reflected ray 803, which is detected from the first eye
image 815 acquired by driving the fifth light source 829, appears larger than a predetermined
reference value, a processor (e.g., the processor 120 in FIG. 1) of the electronic
device 101 may determine that biometric verification is successful. When the size
of the first reflected ray 803 appears smaller than the predetermined reference value
or any reflected ray is not detected, the processor may determine that biometric verification
is unsuccessful.
[0093] A second embodiment 830 shows an example in which the third light source 825 is driven.
When the third light source 825 is driven, a second reflected ray 804 (e.g., a specular
highlight) may appear in an acquired second eye image 835. The third light source
825 is disposed at the second distance from the camera 801, and thus the size of the
second reflected ray 804 may appear relatively smaller compared with the first embodiment
810. The processor 120 may determine biometric liveness, based on whether one second
reflected ray 804 is detected from the second eye image 835 acquired by driving the
third light source 825. For example, when the one second reflected ray 804 is detected
from the second eye image 835 acquired by driving the third light source 825, the
processor 120 may determine that biometric verification is successful. When the second
reflected ray 804 is not detected from the second eye image 835 or when more than
one reflected ray is reflected, the processor 120 may determine that biometric verification
is unsuccessful.
[0094] A third embodiment 850 shows an example in which the second light source 823 and
the third light source 825 are driven. When the second light source 823 and the third
light source 825 are driven, two reflected rays (e.g., a second reflected ray 804
and a third reflected ray 805) (e.g., specular highlights) may appear in an acquired
third eye image 855. The second light source 823 and the third light source 825 are
disposed at the second distance from the camera 801, and thus the size of the reflected
rays 804 and 805 may appear relatively small compared with the first embodiment 810.
The processor 120 may determine biometric liveness, based on whether two reflected
rays 804 and 805 are detected from the third eye image 855 acquired by driving the
second light source 823 and the third light source 825. For example, when the two
reflected rays 804 and 805 are detected from the third eye image 855 acquired by driving
the second light source 823 and the third light source 825, the processor 120 may
determine that biometric verification is successful. When the reflected rays 804 and
805 are not detected from the third eye image 855 or when more or less than two reflected
rays are detected, the processor 120 may determine that biometric verification is
unsuccessful.
[0095] Referring to FIG. 8B, a fourth embodiment 870 shows an example in which the first
light source 821, the second light source 823, and the third light source 825 are
driven. When the first light source 821 to the third light source 825 are driven,
three reflected rays (e.g., a second reflected ray 804, a third reflected ray 805,
and a fourth reflected ray 806) (e.g., specular highlights) may appear in an acquired
fourth eye image 875. The first light source 821 to the third light source 825 are
disposed at the second distance from the camera 801, and thus the size of the second
reflected ray 804 to the fourth reflected ray 806 may appear relatively small compared
with the first embodiment 810. The processor 120 may determine biometric liveness,
based on whether three reflected rays 804, 805, and 806 are detected from the fourth
eye image 875 acquired by driving the first light source 821 to the third light source
825. For example, when the three reflected rays 804, 805, and 806 detected from the
fourth eye image 875 acquired by driving the first light source 821 to the third light
source 825 the processor 120 may determine that biometric verification is successful.
When, the reflected rays 804, 805, and 806 are not detected from the fourth eye image
875, or when more or less than three reflected rays are detected, the processor 120
may determine that biometric verification is unsuccessful.
[0096] The fifth embodiment 890 shows an example in which the first light source 821, the
second light source 823, the third light source 825, and the fourth light source 827
are driven. When the first light source 821 to the fourth light source 827 are driven,
four reflected rays (e.g., a second reflected ray 804, a third reflected ray 805,
a fourth reflected ray 806, and a fifth reflected ray 807) (e.g., specular highlights)
may appear in an acquired fifth eye image 895. The first light source 821 to the fourth
light source 827 are disposed at the second distance from the camera 801, and thus
the size of the second reflected ray 804 to the fifth reflected ray 807 may appear
relatively small compared with the first embodiment 810. The processor 120 may determine
biometric liveness, based on whether four reflected rays 804, 805, 806, and 807 are
detected from the fifth eye image 895 acquired by driving the first light source 821
to the fourth light source 827. For example, when the four reflected rays 804, 805,
806, and 807 are detected from the fifth eye image 895 acquired by driving the first
light source 821 to the fourth light source 827, the processor 120 may determine that
biometric verification is successful. When the reflected rays 804, 805, 806, and 807
are not detected from the fifth eye image 895, or when more or less than four reflected
rays are detected, the processor may determine that biometric verification is unsuccessful.
[0097] According to various embodiments, the detection position or direction of a reflected
ray may be differently detected based on the arrange position of a light source. For
example, when two light sources arranged in the upward/downward direction are driven,
positions of two reflected rays are divided in the upward/downward direction. Alternatively,
when two light sources arranged in the leftward/rightward direction are driven, positions
of two reflected rays are divided in the leftward/rightward direction. When even the
direction of a reflected ray included an eye image is divided due to the development
of an analysis technique, the processor 120 may detect biometric liveness according
to the number of driven light sources as well as the detection position of a reflected
ray based on the arrangement position of a light source.
[0098] FIGS. 9A and 9B illustrate another example of authenticating biometric liveness by
randomly driving a light source in an electronic device according to various embodiments.
[0099] Referring to FIG. 9A, an electronic device (e.g., the electronic device 101 in FIG.
1) according to various embodiments may include a camera 901 (e.g., the camera module
180 in FIG. 1, or the camera modules 250 and 255 in FIGS. 2A and 2B) and at least
one light source 921, 923, 925, or 927 (e.g., the first light source 561 and the second
light source 563 in FIG. 5). The camera 901 may include an under-display camera (UDC)
disposed under a display (e.g., the display module 160 in FIG. 1). A first light source
921, a second light source 923, and a fourth light source 927 may be disposed at a
predetermined distance (e.g., a second distance) from the camera 901, and a third
light source 925 may be disposed at a relatively close distance (e.g., a first distance)
to the camera 901, compared with the other light sources. The first distance may be
shorter than the second distance. The first light source 921 to the fourth light source
927 may be disposed under the display module 160, and IR LEDs may be used therefor.
[0100] According to various embodiments, the camera 901 may be disposed at the upper portion
of the electronic device 101 corresponding to the short length of two parallel side
surfaces of the electronic device 101, and the at least one light source 921, 923,
925, or 927 may be disposed about the camera 901. In the drawing, it is illustrated
that distances by which the first light source 921, the second light source 923, and
the fourth light source 927 are spaced apart from the camera 901 are equal or similar
to each other. However, the distances by which the first light source 921, the second
light source 923, and the fourth light source 927 are spaced apart from the camera
901 may be different from each other. A first embodiment 910 to a fourth embodiment
970 show a front view of the electronic device 101.
[0101] The first embodiment 910 shows an example in which the third light source 925 is
driven. When the third light source 925 is driven, the size of a first reflected ray
903 (e.g., a red-eye effect) in an acquired first eye image 915 may appear relatively
large. The third light source 925 is disposed at the first distance from the camera
901, and thus when the distance between the camera 901 and the third light source
925 is the same short as the first distance, the size of the first reflected ray 903
may be relatively large due to the red-eye effect. When the third light source 925
is driven and when the size of the first reflected ray 903 detected from the acquired
first eye image 915 appears larger than a predetermined reference value, a processor
(e.g., the processor 120 in FIG. 1) of the electronic device 101 may determine that
biometric verification is successful. When the size of the reflected ray appears smaller
than the predetermined reference value, or when the reflected ray is not detected,
the processor may determine that biometric verification is unsuccessful.
[0102] A second embodiment 930 shows an example in which the fourth light source 927 is
driven. When the fourth light source 927 is driven, a second reflected ray 904 (e.g.,
a specular highlight) may appear in an acquired second eye image 935. The fourth light
source 927 is disposed at the second distance from the camera 901, and thus the size
of the second reflected ray 904 may appear relatively small compared with the first
embodiment 910. The processor 120 may determine biometric liveness, based on whether
one second reflected ray 904 is detected from the second eye image 935 acquired by
driving the fourth light source 927. For example, when the one second reflected ray
904 is detected from the second eye image 935 acquired by driving the fourth light
source 927, the processor 120 may determine that biometric verification is successful.
When the second reflected ray 904 is not detected from the second eye image 935, or
when more or one reflected ray is detected, the processor 120 may determine that biometric
verification is unsuccessful.
[0103] Referring to FIG. 9B, a third embodiment 950 shows an example in which the second
light source 923 and the fourth light source 927 are driven. When the second light
source 923 and the fourth light source 927 are driven, two reflected rays (e.g., a
second reflected ray 904 and a third reflected ray 905) (e.g., specular highlight)
may appear in an acquired third eye image 955. The second light source 923 and the
fourth light source 927 are disposed at the second distance from the camera 901, and
thus the size of the second reflected ray 904 and the third reflected ray 905 may
appear relatively small compared with the first embodiment 910. The processor 120
may determine biometric liveness, based on whether two reflected rays 904 and 905
are detected from the third eye image 955 acquired by driving the second light source
923 and the fourth light source 927. For example, when the two reflected rays 904
and 905 are detected from the third eye image 955 acquired by driving the second light
source 923 and the fourth light source 927, the processor 120 may determine that biometric
verification is successful. When the reflected rays 904 and 905 are not detected from
the eye image 955, or when more or less than two reflected rays are detected, the
processor 120 may determine biometric verification is unsuccessful.
[0104] The fourth embodiment 970 shows an example in which the first light source 921, the
second light source 923, and the fourth light source 927 are driven. When the first
light source 921, the second light source 923, and the fourth light source 927 are
driven, three reflected rays (e.g., a second reflected ray 904, a third reflected
ray 905, and a fourth reflected ray 906) (e.g., specular highlight) may appear in
an acquired fourth eye image 975 . The first light source 921, the second light source
923, and the fourth light source 927 are disposed at the second distance from the
camera 901, and thus the size of the second reflected ray 904 to the fourth reflected
ray 906 may appear relatively small compared with the first embodiment 910. The processor
120 may determine biometric liveness, based on whether three reflected rays 904, 905,
and 906 are detected from the fourth eye image 975 acquired by driving the first light
source 921, the second light source 923, and the fourth light source 927. For example,
when the three reflected rays 904, 905, and 906 are detected from the fourth eye image
975 acquired by driving the first light source 921, the second light source 923, and
the fourth light source 927, the processor 120 may determine that biometric verification
is successful. When the reflected rays 904, 905, and 906 are not detected from the
fourth eye image 975, or when more or less than three reflected rays are detected,
the processor 120 may determine that biometric verification is unsuccessful.
[0105] FIG. 10 is a flowchart 1000 illustrating a biometric liveness authentication method
by an electronic device according to various embodiments. Operations in FIG. 10 may
be specified operations of operations 603 to 609 in FIG. 6.
[0106] Referring to FIG. 10, in operation 1001, a processor (e.g., the processor 120 in
FIG. 1) of an electronic device (e.g., the electronic device 101 in FIG. 1) according
to various embodiments may drive a first light source. The first light source may
be disposed close (e.g., a first distance) to a camera (e.g., the camera module 180
in FIG. 1, or the camera modules 250 and 255 in FIGS. 2A and 2B), or may be disposed
to be spaced (e.g., a second distance) apart from the camera. For example, the first
light source may be one of the first light source 821 to the fourth light source 827
in FIGS. 8A and 8B, or may be the fifth light source 829. For example, the first light
source 821, the second light source 823, the third light source 825, and the fourth
light source 827 may be disposed at a predetermined distance (e.g., the second distance)
from the camera 801, and the fifth light source 829 may be disposed at a relatively
close distance (e.g., the first distance) to the camera 801, compared with the first
light source 821 to the fourth light source 827. Alternatively, the first light source
may be one of the first light source 921, the second light source 923, and the fourth
light source 927 in FIGS. 9A and 9B, or may be the third light source 925. The first
light source 921, the second light source 923, and the fourth light source 927 may
be disposed at a predetermined distance (e.g., the second distance) form the camera
901, and the third light source 925 may be disposed at a relatively close distance
(e.g., the first distance) to the camera 901 compared with the other light sources.
[0107] Hereinafter, in the description, an example in which the fifth light source 829 (or
the third light source 925 in FIGS. 9A and 9B) disposed at the first distance from
the camera is driven may be described. In the drawing, only light source driving is
illustrated, but the camera may also be driven during light source driving.
[0108] In operation 1003, the processor 120 may acquire a first face image from the camera
module 180. The first face image may include an eye image. The camera module 180 may
include an under-display camera (UDC) disposed under a display (e.g., the display
module 160 in FIG. 1). For example, for biometric authentication, the processor 120
may drive the camera module 250 disposed at the front surface of the electronic device
101.
[0109] In operation 1005, the processor 120 may analyze the acquired first face image to
determine whether a red-eye effect is detected. In operation 1001, the fifth light
source 829 disposed close to the camera module 180 was driven, and thus a red-eye
effect may occur in a reflected ray included in a user's eye. The processor 120 may
analyze, based on the distance between the first light source and the camera module
180, whether the size of the reflected ray exceeds a predetermined reference value.
For example, the fifth light source 829 disposed close to the camera module 180 was
driven in operation 1001, and thus the processor 120 may determine whether the red-eye
effect is detected, by determining whether a reflected ray is detected from the first
face image and the size of the detected reflected ray appears larger than the predetermined
reference value.
[0110] According to various embodiments, a red-eye effect and a specular highlight may be
different from each other in at least one of size, color, or form. The processor 120
may analyze at least one of the size, color, or the form of the reflected ray detected
from the first face image to determine whether a red-eye effect occurs. For example,
the size of a reflected ray in which the red-eye effect occurs may be larger than
the size of a reflected ray in which the specular highlight appears.
[0111] According to various embodiments, when the distance between the first light source
and the camera module 180 has a value equal to or smaller than a distance reference
value (e.g., the fifth light source 829 in FIGS. 8A and 8B or the third light source
925 in FIGS. 9A and 9B), the processor 120 may determine whether the size of a reflected
ray detected from an eye in the first face image appears larger than the predetermined
reference value. The distance reference value may be configured based on the spacing
distance between the light source and the camera, and may be greater than the first
distance and smaller than the second distance. According to various embodiments, if
the distance between the first light source and the camera module 180 has a value
equal to or smaller than the distance reference value, the processor 120 may perform
operation 1015 when a reflected ray is not detected from the eye in the first face
image or when a red-eye effect is not detected (e.g., the size of a reflected ray
is smaller than the predetermined reference value). Alternatively, when a reflected
ray having a size smaller than the predetermined reference value is detected, the
processor 120 may adjust the intensity of the first light source to acquire a face
image again and determine biometric liveness.
[0112] In operation 1007, the processor 120 may drive a second light source. The second
light source, which is a light source different from the first light source, may be
disposed at a position different of that of the first light source. The processor
120 may randomly drive different light sources included in the electronic device 101,
thereby determining biometric liveness. Like the first light source 821 to the fourth
light source 827 in FIGS. 8A and 8B or the first light source 921, the second light
source 923, and the fourth light source 927 in FIGS. 9A and 9B, the second light source
may be a light source disposed at a predetermined distance (e.g., the second distance)
from the camera module 180.
[0113] According to various embodiments, even when the red-eye effect has been detected
in operation 1005, the processor 120 may further perform operations 1007 to 1011,
thereby improving the security. Alternatively, the processor 120 may perform operations
1007 to 1011, based on the security level (or type) of biometric authentication. For
example, if biometric authentication is requested in relation to a financial transaction
or a payment service, the processor 120 may further perform operations 1007 to 1011
in order to improve the security even when the red-eye effect has been detected in
operation 1005. Alternatively, when biometric authentication is requested in relation
to unlocking the electronic device 101, the processor 120 may perform operation 1013
or 1015 without performing operations 1007 to 1011.
[0114] In operation 1009, the processor 120 may acquire a second face image from the camera
module 180. The second face image may include an eye image. The second face image
may be different from the first face image acquired in operation 1003, and a face
image may be acquired again by randomly driving the light source.
[0115] In operation 1011, the processor 120 may analyze the acquired second face image to
determine whether a specular highlight is detected. The second light source was driven
in operation 1007, and thus a specular highlight may be detected in a reflected ray
included in a user's eye. According to various embodiments, a red-eye effect and a
specular highlight may be different from each other in at least one of size, color,
or form. The processor 120 may analyze at least one of the size, color, or form of
a reflected ray detected from the second face image to determine whether the specular
highlight is detected.
[0116] According to various embodiments, when the distance between the second light source
and the camera module 180 exceeds a distance reference value (e.g., the first light
source 821 to the fourth light source 827 in FIGS. 8A and 8B, or the first light source
921, the second light source 923, and the fourth light source 927 in FIG. 9A and 9B),
the processor 120 may determine whether the size of a reflected ray included from
an eye included in the second face image appears smaller than the predetermined reference
value.
[0117] The processor 120 may perform operation 1013 when the specular highlight is detected
from the eye in the second face image, and may perform operation 1015 when a reflected
ray is not detected from the eye in the second face image or when the size of a reflected
ray appears larger (e.g., a red-eye effect) than the predetermined reference value.
The first light source or the second light source is an IR light source, and thus
even when the light source is driven, the user may not identify whether the light
source has been driven.
[0118] In operation 1013, the processor 120 may determine biometric liveness. When biometric
liveness has been determined in both operations 1005 and 1011, the processor 120 may
finally determine that the biometric authentication is successful. According to various
embodiments, the processor 120 may configure the number of biometric liveness determination
operations, based on the security level (or type) of biometric authentication. For
example, when the security level is a first level (e.g., high), biometric liveness
determination may be performed three times (e.g., operations in FIG. 10 and operations
1107 to 1113 in FIG. 11). When the security level is a second level (e.g., intermediate),
biometric liveness determination may be performed two times (e.g., FIG. 10 and FIG.
11). When the security level is a third level (e.g., low), biometric liveness determination
may be performed once (e.g., one of operations 1001 to 1005, or operations 1007 to
1011 in FIG. 10, or operations 1107 to 1111 in FIG. 11). Alternatively, if there are
two security levels, biometric liveness determination may be performed two times when
the security level is a first level (e.g., high), and biometric liveness determination
may be performed once when the security level is a second level (e.g., low).
[0119] In operation 1015, the processor 120 may determine that a living body is fake. When
a red-eye effect is not detected from the eye in the face image, or when a specular
highlight is not detected, the processor 120 may determine that biometric verification
is unsuccessful. In the drawing, it is illustrated that operation 1015 is performed
when the result is No after operation 1005 is performed. However, when the result
is No after operation 1005 is performed, operation 1007 may be performed. There may
be an error in the result of the face image analysis. Therefore, when a reflected
ray (e.g., a red-eye effect) is not detected in operation 1005, biometric liveness
may be determined once again, and a living body may be determined to be fake when
a specular highlight is not detected. This may vary depending on the setting by the
user or the setting of the electronic device 101.
[0120] According to various embodiments, the processor 120 may further perform operations
1107 to 1115 in FIG. 11 after completing the operations in FIG. 10. For example, based
on the security level, the processor 120 may perform one of operations 1001 to 1005
or operations 1007 to 1011 in FIG. 10, or operations 1107 to 1111 in FIG. 11, may
perform one of the operations in FIG. 10 or 11, or may perform the operations in FIG.
10 and operations 1107 to 1113 in FIG. 11.
[0121] FIG. 11 is a flowchart 1100 illustrating a biometric liveness authentication method
of an electronic device according to various embodiments. Operations in FIG. 11 may
be specified operations of operations 603 to operation 609 in FIG. 6.
[0122] Referring to FIG. 11, in operation 1101, a processor (e.g., the processor 120 in
FIG. 1) of an electronic device (e.g., the electronic device 101 in FIG. 1) according
to various embodiments may drive a second light source. The second light source may
be disposed close (e.g., a first distance) to a camera (e.g., the camera module 180
in FIG. 1, or the camera modules 250 and 255 in FIGS. 2A and 2B), or may be disposed
to be spaced (e.g., a second distance) apart from the camera. For example, the second
light source may be one the first light source 821 to the fourth light source 827
in FIG. 8A and 8B, or may be the fifth light source 829. For example, the first light
source 821, the second light source 823, the third light source 825, and the fourth
light source 827 may be disposed a predetermined distance (e.g., the second distance)
from the camera 801, and the fifth light source 829 may be disposed at a relatively
close distance (e.g., the first distance) to the camera 801, compared with the first
light source 821 to the fourth light source 827. Alternatively, the second light source
may be one of the first light source 921, the second light source 923, and the fourth
light source 927 in FIGS. 9A and 9B, or may be the third light source 925. The first
light source 921, the second light source 923, and the fourth light source 927 may
be disposed a predetermined distance (e.g., the second distance) from the camera 901,
and the third light source 925 may be disposed at a relatively close distance (e.g.,
the first distance) to compared with the other light sources.
[0123] Hereinafter, in the description, an example in which the second light source 823
(or the second light source 923 in FIG. 9A and 9B) disposed at the second distance
from the camera is driven may be described. In the drawing, only light sourcing driving
is illustrated, but the camera may also be driven while the light source is driven.
[0124] In operation 1103, the processor 120 may acquire a first face image from the camera
module 180. The first face image may include an eye image. The camera module 180 may
include an under-display camera (UDC) disposed under a display (e.g., the display
module 160 in FIG. 1). For example, for biometric authentication, the processor 120
may drive the camera module 250 disposed at the front surface of the electronic device
101.
[0125] In operation 1105, the processor 120 may analyze the first face image to determine
whether one specular highlight is detected. In operation 1101, the second light source
823 disposed to be spaced apart from the camera module 180 was driven, and thus a
reflected ray included in a user's eye may be a specular highlight. According to various
embodiments, a red-eye effect and a specular highlight may be different from each
other in at least one of size, color, or form. The processor 120 may analyze at least
one of the size, color, or form of a reflected ray detected from the first face image
to determine whether a specular highlight is detected.
[0126] Operations 1101 to 1105 in FIG. 11 are identical or similar to operations 1107 to
1011 in FIG. 10.
[0127] According to various embodiments, when the distance between the second light source
and the camera module 180 exceeds a distance reference value, the processor 120 may
determine whether the size of a reflected ray detected from an eye in the first face
image appears smaller than a predetermined reference value. The distance reference
value may be configured based on the spacing distance between the light source and
the camera module 180, and may be greater than the first distance and smaller than
the second distance. According to various embodiments, when the distance between the
second light source and the camera module 180 exceeds the distance reference value,
the processor 120 may perform operation 1115 when a reflected ray is not detected
from the eye in the first face image, or when two or more reflected rays are detected,
or when the size of a reflected ray is larger than the predetermined reference value.
[0128] In operation 1107, the processor 120 may drive the second light source and a third
light source. The third light source is a light source different from the second light
source, and may be disposed in a position different from the position of the second
light source. The processor 120 may randomly drive different light sources included
in the electronic device 101 to determine biometric liveness. Like the first light
source 821 to the fourth light source 827 in FIGS. 8A and 8B, or like the first light
source 921, the second light source 923, and the fourth light source 927 in FIGS.
9A and 9B, the third light source may be a light source disposed at the predetermined
distance (e.g., the second distance) from the camera module 180. Hereinafter, in relation
to the third light source, a description may be made of an example in which the third
light source 825 in FIGS. 8A and 8B or the fourth light source 927 in FIGS. 9A and
9B are driven.
[0129] According to various embodiments, even when one specular highlight has been detected
in operation 1105, the processor 120 may further perform operations 1107 to 1111,
thereby improving the security. Alternatively, the processor 120 may further perform
operations 1107 to 1111, based on the security level (or type) of biometric authentication.
For example, if biometric authentication is requested in relation to a financial transaction
or a payment service, the processor 120 may further operations 1107 to 1111 in order
to improve the security even when one specular highlight has been detected. Alternatively,
when biometric authentication is requested in relation to unlocking the electronic
device 101, the processor 120 may perform operation 1113 or 1115 without performing
operations 1107 to 1111.
[0130] In operation 1109, the processor 120 may acquire a second face image from the camera
module 180. The second face image may include an eye image. The second face image
is different from the first face image acquired in operation 1103, and a face image
may be acquired again by randomly driving the light sources.
[0131] In operation 1111, the processor 120 may analyze the second face image to determine
whether two specular highlights are detected. The second light source and the third
light source were driven in operation 1107, and thus two specular highlight may be
detected in a reflected ray included in the user's eye. The processor 120 may analyze
at least one of the size, color, or form of a reflected ray detected from the second
face image to determine whether two specular highlights are detected.
[0132] The processor 120 may perform operation 1113 when two specular highlights are detected
from an eye in the second face image, and may perform operation 1115 when a reflected
ray is not detected from the eye in the second face image, or when the size of a reflected
ray appears larger (e.g., a red-eye effect) than a predetermined reference value,
or more or less than two reflected rays are detected. The second light source and
the third light source are IR light sources, and thus even when the light sources
are driven, the user may not identify whether the light source have been driven.
[0133] In operation 1113, the processor 120 may determine biometric liveness. When biometric
liveness has been determined in both operations 1105 and 1111, the processor 120 may
finally determine that biometric authentication is successful. According to various
embodiments, the processor 120 may configure the number of biometric liveness determination
operations, based on the security level (type) of biometric authentication. For example,
when the security level is a first level (e.g., high), biometric liveness determination
may be performed three times. When the security level is a second level (e.g., intermediate),
biometric liveness determination may be performed two times. When the security level
is a third level (e.g., low), biometric liveness determination may be performed once.
Alternatively, if there are two security levels, biometric liveness determination
may be performed two times when the security level is a first level (e.g., high),
and biometric liveness determination may be performed once when the security level
is a second level (e.g., low).
[0134] In operation 1115, the processor 120 may determine that biometric verification is
unsuccessful. When the number of specular highlights detected from the eye in the
face image does not correspond to the number of driven light sources, the processor
120 may determine that biometric verification is unsuccessful. In the drawing, it
is illustrated that after operation 1105 is performed, when the result thereof is
No, operation is performed. However, after operation 1105 is performed, when the result
is No, operation 1107 may be performed. There may be an error in the result of the
face image analysis. Therefore, when a reflected ray is not detected in operation
1105, biometric liveness may be determined once again, and a living body may be determined
to be fake when a reflected ray is not detected two times or when the number of specular
highlights does not correspond to the number of driven light sources. This may vary
depending on the setting by the user or the setting of the electronic device 101.
[0135] FIG. 12 is a flowchart 1200 of a biometric-authentication and liveness-authentication
method of an electronic device according to various embodiments. Operations in FIG.
12 may be specified operations of operations 605 to 609 in FIG. 6.
[0136] Referring to FIG. 12, in operation 1201, a processor (e.g., the processor 120 in
FIG. 1) of an electronic device (e.g., the electronic device 101 in FIG. 1) according
to various embodiments may acquire a face image from the camera module 180. The face
image may include an eye image. The camera module 180 may include an under-display
camera (UDC) disposed under a display (e.g., the display module 160 in FIG. 1). For
example, for biometric authentication, the processor 120 may drive the camera module
250 disposed at the front surface of the electronic device 101.
[0137] In operation 1203, the processor 120 may perform biometric authentication based on
the acquired face image. The biometric authentication, which is different form biometric
liveness determination, may be determining whether the face image corresponds to a
user's biometric information (e.g., a face, a fingerprint, or an iris) stored in a
memory (e.g., the memory 130 in FIG. 1). In the drawing, it is illustrated that operation
1203 is performed before operation 1205. However, operation 1203 may be simultaneously
performed with operation 1205, may be performed after operation 1205, or may be performed
after operation 1207. The disclosure is not limited by the drawing description.
[0138] In operation 1205, the processor 120 may analyze the face image, based on a driven
light source. When one light source has been driven, the processor 120 may analyze
whether a reflected ray is included in an eye in the face image. The reflected ray
included in the eye may imply a specular highlight. According to various embodiments,
when the distance between a camera (e.g., an image sensor) and a light source is short,
a red-eye effect may occur and thus the size of a reflected ray may be large. When
the distance between the camera and the light source increase, a specular highlight
may appear and thus the size of a reflected ray may be small. The processor 120 may
recognize a face from the acquired face image, and may detect an eye, based on the
face recognition, to perform an operation of determining biometric liveness. Alternatively,
the processor 120 may detect an eye from the face image to perform an operation of
determining biometric liveness. Operation 1205 is identical or similar to operation
607 in FIG. 6, and thus a detailed description thereof will be omitted.
[0139] In operation 1207, the processor 120 may determine biometric liveness, based on the
analysis result. The biometric liveness may be determining whether the number of reflected
rays from a face image corresponds to the number of driven light sources. For example,
when one light source has been driven, the processor 120 may determine whether the
number of reflected rays detected from an eye in the face image is one or whether
the size of a reflected ray exceeds a predetermined reference value. Alternatively,
when two light sources have driven, the processor 120 may determine whether the number
of reflected rays detected from an eye in the face image is two.
[0140] In operation 1209, the processor 120 may perform a function related to biometric
authentication. The function related to biometric authentication has been requested
in operation 601. For example, the processor 120 may unlock the electronic device
101, may perform a financial transaction service or a payment service, or may perform
a configured function of an application. When biometric authentication and biometric
liveness determination are successful, the processor 120 may allow a function corresponding
to the biometric authentication requested in operation 601. When biometric authentication
and biometric liveness determination are unsuccessful, the processor 120 may not allow
a function corresponding to the biometric authentication requested in operation.
[0141] A method for operating an electronic device (e.g., the electronic device 101 in FIG.
1) according to various embodiments may include driving a camera module (e.g., the
camera module 180 in FIG. 1 or the camera modules 250 and 255 in FIGS. 2A and 2B),
disposed under a display (e.g., the display module 160 in FIG. 1 or the display 230
in FIGS. 2A and 2B) of the electronic device, and at least one light source (e.g.,
the first light source 821 to the fifth light source 829 in FIGS. 8A and 8B, or the
first light source 921 to the fourth light source 927 in FIGS. 9A and 9B) disposed
to correspond to the camera module, in response to a request for biometric authentication,
acquiring a face image from the camera module, analyzing the face image, based on
the driven at least one light source, and performing biometric authentication based
on the analysis result.
[0142] The at least one light source may include a first light source (e.g., the fifth light
source 829 in FIGS. 8A and 8B, or the third light source 925 in FIGS. 9A and 9B) disposed
at a first distance from the camera module, and a second light source (e.g., the first
light source 821 to the fourth light source 827 in FIGS. 8A and 8B, or the first light
source 921, the second light source 923, and the fourth light source 927 in FIGS.
9A and 9B) disposed at a second distance from the camera module, and the first distance
may be configured to be shorter than the second distance.
[0143] The analyzing may include determining whether a red-eye effect is detected from an
eye included in the face image when the first light source is driven, or determining
whether a specular highlight is detected from the eye included in the face image when
the second light source is driven.
[0144] The method may include determining whether the size of a reflected ray detected from
the eye appears larger than a predetermined reference value when the first light source
is driven, determining biometric verification to be successful when the size of the
reflected ray is larger than the predetermined value, and determining biometric verification
to be unsuccessful when the reflected ray is not detected from the eye or when the
size of the reflected ray is smaller than the determined reference value.
[0145] The method may include determining whether the size of a reflected light detected
from the eye included in the face image appears smaller than a predetermined reference
value when the second light source is driven, determining biometric verification to
be successful when the size of the reflected ray is smaller than the predetermined
reference value, and determining biometric verification to be unsuccessful when the
reflected ray is not detected from the eye or when the size of the reflected ray is
larger than the predetermined reference value.
[0146] The electronic device may further include a third light source disposed at the second
distance from the camera module. The method may include acquiring a first face image
by driving one of the second light source or the third light source, determining whether
the number of reflected rays detected from an eye included in the first face image
is one, acquiring a second face image by driving the second light source and the third
light source when the number of the reflected rays detected from the eye included
in the first face image is one, determining whether the number of reflected rays detected
from an eye included in the second face image is two, determining biometric verification
to be successful when the number of reflected rays detected from the eye included
in the second face image is two, and determining biometric verification to be unsuccessful
when the reflected rays are not detected from the eye included in the second face
image or when more or less than two reflected rays are detected.
[0147] The at least one light source may be an IR LED.
[0148] The biometric authentication may include biometric authentication of determining
whether the acquired face image matches a face image stored in the memory, and determining
biometric liveness, based on the driven light source.
[0149] The method may further include performing a function related to requested biometric
authentication when the number of reflected rays detected from an eye included in
the face image corresponds to the number of the driven light sources and when the
acquired face image corresponds to the face image stored in the memory.
[0150] The method may further include determining, based on a security level of the requested
biometric authentication, the number of times biometric liveness is determined based
on the driven light source.
[0151] Various embodiments disclosed in the specification and the drawings are merely particular
examples provided for easily describing the technical matters of the disclosure and
contributing to understanding the disclosure, and do not limit the scope of the disclosure.
Therefore, it should be construed that all modifications or modified forms capable
of being derived from the technical idea of the disclosure in addition to the embodiments
disclosed herein are included in the scope of the disclosure.